What are the effects of giving a man extra testosterone?
As I’ve studied testosterone over the years, I’ve been struck by the number of negative side effects of supplemental, exogenous testosterone.
Giving a man testosterone gives him more estrogen.
One of the many functions of testosterone is to turn into estrogen.
Higher testosterone often leads to higher estrogen levels.
It’s been long established that men can function quite well sexually and every other way with fairly low testosterone.
But high estrogen levels affect everything badly.
They cause ED, low motivation, and belly fat.
High estrogen levels have even been linked to diseases as serious as diabetes and cancer.
With that as background let’s look at the first study where they gave men extra testosterone.
These are 60-year-old to 80-year-old men.
They had testosterone levels below about 400.
As you may know, 400 is low, but not what is known as hypogonadal, or ultralow.
So these men would ordinarily not necessarily have received supplemental testosterone except for participation in the study.
This was a pretty good study.
It was a randomized, controlled trial.
So some of the men received testosterone and some of the men received a placebo.
This was done so that nobody knew whether they were getting the real testosterone or the placebo.
This is the gold standard for these kinds of studies.
The results of this study were quite striking.
The big downside of the study was that it was only a six-month test.
But even so, let’s look at some striking results.
Almost half the men who were taking testosterone got metabolic syndrome.
This metabolic syndrome is a combination of obesity, high blood pressure, atherosclerosis, and diabetes.
47% of men getting the testosterone were diagnosed with metabolic syndrome.
Far fewer men who were only receiving the placebo got metabolic syndrome.
So these participants were far better off.
You may remember that brain function is thought to improve with higher testosterone.
It’s also associated with higher bone density.
So what did the study find as far as cognition and bone mineral density?
Cognitive function and bone mineral density did not change.
No difference between the group getting the placebo, and the group getting testosterone.
Now, we know that testosterone supplementation is not necessarily going to improve our bodies metabolically.
It may not help in almost any other way either.
This study did not cover sexual function.
But based on many other studies, it is a safe bet that sexual function did not improve with the testosterone supplementation.
In all probability libido was a bit higher, but erections were probably no better.
Now let’s look at a trial where testosterone was given to men who were sick at the VA hospital with heart disease.
This trial was to determine if these men live longer with testosterone supplementation.
All these men had had a heart attack, or were highly susceptible, and they all had low testosterone levels.
This study followed up with these men at least two years or more on average.
And the results were striking:
testosterone use was associated with increased risk of adverse outcomes including all-cause mortality, heart attack, and stroke.
Why does supplemental testosterone increase the risk of heart attack and death?
The study authors speculate about why testosterone supplementation seems to harm patients.
First of all, it increases platelet density and platelet aggregation.
Perhaps the platelets contribute to plaque formation and the possibility of a heart attack.
Second, testosterone turns into DHT, and too much DHT can promote atherosclerosis and inflammation.
Finally, testosterone has been shown to “worsen sleep disordered breathing among patients with severe sleep apnea”, which is another risk factor.
Why did this study show something different than other studies which showed benefits to taking testosterone?
This study shows an answer:
Most of the other studies were small, enrolled patients of different ages, and were of variable duration.
I would say that there’s another huge reason that this study showed that testosterone supplementation is harmful.
This study was not paid for by the drug companies.
The study was financed by the Veterans Administration.
This isn’t the case with most of the studies showing the benefits of testosterone supplementation.
These other studies were funded by the big drug companies.
These companies want to be able to push testosterone on everybody to increase their profits.
Effect of Testosterone Supplementation on Functional Mobility, Cognition, and Other Parameters in Older Men – A Randomized Controlled Trial
Association of Testosterone Therapy With Mortality, Myocardial Infarction, and Stroke in Men With Low Testosterone Levels